Molecular properties of linear amino acids in water.

Four linear amino acids of increased separation of the carboxyl and amino groups, namely glycine (aminoacetic acid), ß-alanine (3-aminopropanoic acid), GABA (4-aminobutanoic acid) and DAVA (5-aminopentanoic acid), have been studied by quantum chemical ab initio and DFT methods including the solvent effect in order to get electronic structure and molecular descriptors, such as ionisation energy, electron affinity, molecular electronegativity, chemical hardness, electrophilicity index, dipole moment, quadrupole moment and dipole polarizability. Thermodynamic functions (zero-point energy, inner energy, enthalpy, entropy, and the Gibbs energy) were evaluated after the complete vibrational analysis at the true energy minimum provided by the full geometry optimization. Reaction Gibbs energy allows evaluating the absolute redox potentials on reduction and/or oxidation. The non-local non-additive molecular descriptors were compared along the series showing which of them behave as extensive, varying in match with the molar mass and/or separation of the carboxyl and amino groups. Amino acidic forms and zwitterionic forms of the substances were studied in parallel in order to compare their relative stability and redox properties. In total, 24 species were investigated by B3LYP/def2-TZVPD method (M1) including neutral molecules, molecular cations and molecular anions. For comparison, MP2/def2-TZVPD method (M2) with full geometry optimization and vibrational analysis in water has been applied for 12 species; analogously, for 24 substances, DLPNO-CCSD(T)/aug-cc-pVTZ method (M3) has been applied in the geometry obtained by MP2 and/or B3LYP. It was found that the absolute oxidation potential correlates with the adiabatic ionisation energy; the absolute reduction potential correlates with the adiabatic electron affinity and the electrophilicity index. In order to validate the used methodology with experimental vertical ionisation energies and vibrational spectrum obtained in gas phase, calculations were done also in vacuo.

Electronic structure and molecular properties of nitisinone and mesotrione in water.

CONTEXT: Nitisinone is a medium-sized organic molecule that is used in treating hereditary tyrosinemia type 1 (HT-1). The structurally analogous mesotrione, however, is used as a pesticide/herbicide. What molecular properties are responsible for the similarity/dissimilarity of these molecules is investigated here. The solvent effect reduces the electron affinity to rather negative values and causes the negative electron affinity which manifests itself in a very high positive absolute reduction potential. METHODS: B3LYP method was utilized for a geometry optimization of nitisinone and mesotrione in their neural and ionized (L0, L+, L-) forms of 6 structures. The calculations were conducted in water as a solvent using conductor-like polarizable continuum model (CPCM), nitisinone also in vacuo. The complete vibrational analysis at the true energy minimum allows evaluating the thermodynamic functions with focus to the zero-point energy and overall entropic term. The change of the Gibbs energy on reductions and/or oxidation facilitates evaluating the absolute reduction and absolute oxidation potentials. Also, DLPNO-CCSD(T) method that involves the major part of the correlation energy has been applied to nitisinone and mesotrione and their molecular ions.

Effect of Solvation on Glycine Molecules: A Theoretical Study.

Ab initio calculations of HF+MP2 and DFT-B3LYP quality have been used in calculating the molecular geometries and properties of neutral and charged molecules of glycine in amino acid as well as zwitterionic forms. A traditional set of molecular descriptors has been enriched by the molecular chemical potential, expressed via the Mulliken electronegativity, and Pearson's chemical hardness. In the global energy minimum, the complete vibrational analysis allowed evaluating the standard Gibbs energy and related thermodynamic quantities.

Ab initio study of molecular properties of l-tyrosine.

CONTEXT: l-Tyrosine is a naturally occurring agent that acts as a precursor in biosynthesis of monoaminergic neurotransmitters in brain such as dopamine, adrenaline, noradrenaline, and hormones like thyroxine and triiodothyronine. While l-tyrosine in vacuo adopts the canonical aminoacid form with -NH2 and -COOH functional groups, from neutral solutions, is crystallizes in the zwitterionic form possessing -NH3+ and -COO- groups. As l-tyrosine is non-innocent agent with respect to redox processes, redox ability in water expressed by the absolute oxidation and reduction potentials is investigated. The cluster analysis applied to a set of nine related neurotransmitters and trace amines confirms that l-tyrosine is mostly similar to aminoacid forms of phenylalanine, octopamine, and noradrenaline. METHODS: The energetic data at the Hartree-Fock MO-LCAO-SCF method has been conducted using def2-TZVP basis set, and improved by the many-body perturbation theory using the MP2 correction to the correlation energy. For the aminoacid form and the zwitterionic form of l-tyrosine, a set of molecular descriptors has been evaluated (ionization energy, electron affinity, molecular electronegativity, chemical hardness, electrophilicity index, dipole moment, quadrupole moment, and dipole polarizability). The solvent effect (CPCM) is very expressive to the zwitterionic form and alters the sign of the electron affinity from positive to negative values. In parallel, density-functional theory with B3LYP variant in the same basis set has been employed for full geometry optimization of the neutral and ionized forms of l-tyrosine allowing assessing the adiabatic (a) ionization/affinity processes. The complete vibrational analysis enables evaluating thermodynamic functions such as the inner energy, enthalpy, entropy, Gibbs energy, and consequently the absolute oxidation and reduction potentials. Of applied methods, the most reliable are B3LYP(a) results that account to the correlation energy and the electron and nuclear relaxation during the ionization/affinity processes.

Factors Associated with Non-Attendance at Dental Preventive Care in Slovak High School Students.

This study aimed to determine the factors associated with the avoidance of dental preventive care in high school students and their parents in the framework of The Youth and Parents Risk Factor Behavior Survey in Slovakia, the ongoing cross-sectional school-based survey of students and their parents or legal representatives. The data were collected using two separate standardized questionnaires: (i) the questionnaire for students (n = 515) and (ii) the questionnaire for parents (n = 681). The study group included 57 high school students (54.4% males) who did not visit the dentist for preventive care in the previous year. The control group included 458 students (35.8% males) who visited a dentist for preventive care at least once in the previous year. A significantly higher number of males (54.4%), older adolescents, and young adults (21.8%; 20.0%) were not visiting dental preventive care regularly. Incomplete family (56.1%), stressful situations at home (17.5%), and feeling unwell were the factors contributing to the avoidance of dental preventive care. More than 34.5% of adolescents and young adults were not visiting either dental preventive care or pediatric preventive care (adjusted odds ratio (AOR) = 5.14; 95% confidence interval (CI) = 2.40, 10.99). Children of divorced mothers and mothers with household income lower than EUR 900 had significantly higher dental care avoidance in bivariate analysis. A significantly higher percentage of fathers from the exposed group were not visiting dental preventive care regularly (47.8%, p < 0.05). The results of the study can be used as an educational intervention step focusing on the parental influence on adolescent and young adults' behavior and as a challenge for the improvement of dental preventive care in older adolescents and young adults.

Social Noise Exposure in a Sample of Slovak University Students.

PURPOSE: Social noise exposure is currently an emerging problem in adolescents and young adults. Various leisure time activities may be responsible for hearing impairment (temporary or permanent hearing threshold shift or hearing loss). The study aimed to quantify environmental noise from various sources-voluntary (social) noise (personal music players (PMPs), high-intensity noise exposure events), and road traffic noise and to detect hearing disorders in relation to individual listening to PMPs in the sample of young adults living and studying in Bratislava, the capital city of Slovakia. METHODS: The study included 1003 university students (306 men and 697 women, average age 23.1 ± 2) living in Bratislava for 4 or more years; 347 lived in the student housing facility exposed to road traffic noise (LAeq = 67.6 dB) and 656 in the control one (LAeq = 53.4 dB). Respondents completed a validated ICBEN 5-grade scale "noise annoyance questionnaire". In the exposed group a significant source of annoyance was road traffic noise (p < 0.001), noise from entertainment facilities (p < 0.001), industrial noise (p < 0.001), and noise from neighboring flats (p = 0.003). The exposure to PMPs was objectified by the conversion of the subjective evaluation of the volume setting and duration. With the cooperation of the Ear, Nose and Throat (ENT)specialist, we arranged audiometric examinations on the pilot sample of 41 volunteers. RESULTS: From the total sample of respondents, 79.2% reported the use of a PMP in the course of the last week, and the average time was 285 minutes. There was a significant difference in PMP use between the road traffic noise-exposed (85.6%) and the control group (75.8%) (p = 0.01). Among PMP users 30.7% exceeded the lower action value (LAV) for industry (LAeq,8h = 80 dB). On a pilot sample of volunteers (n = 41), audiometry testing was performed indicating a hearing threshold shift at higher frequencies in 22% of subjects. CONCLUSIONS: The results of the study on a sample of young healthy individuals showed the importance of exposure to social noise as well as to road traffic noise and the need for prevention and intervention.

Maternal Body Mass Index and Gestational Weight Gain and Their Association with Pregnancy Complications and Perinatal Conditions.

This study aimed to evaluate the impact of selected pregnancy pathologies statistically depending on overweight/obesity and excessive maternal weight gain during pregnancy on women who gave birth in the years 2013-2015 at the Second Department of Gynecology and Obstetrics at the University Hospital in Bratislava, Slovakia. In a retrospective study, we analyzed data gathered from the sample, which consisted of 7122 women. Our results suggest a statistically significant, higher risk for the groups of women with overweight and obesity and gestational hypertension (adjusted odds ratio (AOR) = 15.3; 95% CI 9.0-25.8 for obesity), preeclampsia (AOR = 3.4; 95% CI 1.9-6.0 for overweight and AOR = 13.2; 95% CI 7.7-22.5 for obesity), and gestational diabetes mellitus (AOR = 1.9; 95% CI 1.2-2.9 for overweight and AOR = 2.4; 95% CI 1.4-4.0 for obesity). A higher incidence of pregnancies terminated by cesarean section was observed in the group of obese women. Gestational weight gain above IOM (Institute of Medicine) recommendations was associated with a higher risk of pregnancy terminated by C-section (AOR = 1.2; 95% CI 1.0-1.3), gestational hypertension (AOR = 1.7; 95% CI 1.0-2.7), and infant macrosomia (AOR = 1.7; 95% CI 1.3-2.1). Overweight and obesity during pregnancy significantly contribute to the development of pregnancy pathologies and increased incidence of cesarean section. Systematic efforts to reduce weight before pregnancy through prepregnancy dietary counseling, regular physical activity, and healthy lifestyle should be the primary goal.

Self-Reported Exposure to ETS (Environmental Tobacco Smoke), Urinary Cotinine, and Oxidative Stress Parameters in Pregnant Women-The Pilot Study.

BACKGROUND: Exposure to ETS (environmental tobacco smoke) is one of the most toxic environmental exposures. OBJECTIVE: To investigate the association of ETS with physiological, biochemical, and psychological indicators, as well as with urine antioxidant capacity (AC) and oxidative damage to lipids in a pilot sample of healthy pregnant women. METHODS: Exposure to ETS was investigated via a validated questionnaire, and urine cotinine and the marker of oxidative damage to lipids via 8-isoprostane concentrations using an ELISA kit. Urine AC was determined by the spectrophotometric Trolox-equivalent antioxidant capacity (TEAC) method. From a sample of pregnant women (n = 319, average age 30.84 ± 5.09 years) in 80, the levels of cotinine and oxidative stress markers were analyzed. RESULTS: Among the 80 pregnant women, 5% (7.4% confirmed by cotinine) reported being current smokers and 25% reported passive smoking in the household (18.8% confirmed by cotinine). The Kappa was 0.78 for smokers and 0.22 for ETS-exposed nonsmokers. Pregnant women in the ETS-exposed group had significantly reduced AC compared to both the nonsmoker (ETS-) and the smoker groups (p < 0.05). Nonsmokers had significantly lower levels of 8-isoprostane than smokers (p < 0.01) and ETS-exposed nonsmokers (p < 0.05). Correlations between urine levels of cotinine and AC were positive in ETS-exposed nonsmokers. CONCLUSION: A harmful association of active and passive smoking and oxidative stress parameters among pregnant women has been indicated.

The Comorbidity of Focal Epilepsy and Narcolepsy Type 1 - Two Case Reports.

The aim of this study is to remind the possibility of co-occurrence of epilepsy and narcolepsy. In the first case report, narcolepsy type 1 was diagnosed in 29-year-old female. After one year of the treatment with modafinil a new episodes of automatic behavior appeared. Patient was reevaluated and the diagnosis of focal epilepsy with partial complex seizures was established. Patient was treated with modafinil and lamotrigine and became seizure-free. In the second case report a 21-year-old female was referred with a typical history of narcolepsy type 1, but also with atypical episodes of gazing and automatic behavior with amnesia for these episodes. Narcolepsy type 1 and focal epilepsy was diagnosed. Some clinical symptoms of narcolepsy (cataplexy, automatic behavior, episodes of sleep attacks) need to be carefully analyzed by EEG and video-EEG not to overlook the epilepsy.

The quest of cavum septi pellucidi: obscure chance event discovery or the result of some encoded disturbance? Developmental cerebral dysplasias, cavum septi pellucidi and epilepsy: clinical, MRI and electrophysiological study.

OBJECTIVES: Developmental cerebral dysplasias are frequent causes of epilepsy. The early stage of gestation, mainly the period of neural crest separation and neuroblast migration (disturbance of midline structures, heterotopias, cortical dysplasias and disturbance of the ventricular and vascular formation), may be considered as a cause of serious cerebral dysplasia. The aim of the study was focused on frequent simultaneous occurrences of epileptic seizures and the defect or abnormality of the ventricular system - cavum septi pellucidi (CSP). MATERIAL AND METHOD: In our study the clinical symptoms, EEG and somatosensory evoked potentials (SEP's) following median nerve stimulation and MRI pictures in the group of patients with CSP (n= 35), were analyzed. In the SEP analysis, a control group of normal, healthy volunteers (n = 40) and a group of age matched patients with epileptic seizures of different origin, without structural lesions evident on MRI (n=21), were used. RESULTS: Analysis of the patient population with CSP (CSP was confirmed by MRI) showed that approximately in 2/3 cases, different types of cranio-cerebral dysplasias were evident on MRI. More than 2/3 of the patients with CSP showed epilepsy and an abnormal EEG record, however, focal EEG changes were seen more frequently in the group of patients with epilepsy without CSP, than in patients with CSP. The SEP's in patients with CSP showed a statistically significant prolongation of latency of thalamic P15 waves, however these changes were not present in the group of patients with epilepsy of a different origin. CONCLUSIONS: In a group of patients with CSP, dysplastic MRI changes, together with the prolongation of thalamic wave latencies according SEP, were examined. These clinical symptoms may be considered the result of disturbances of early gestation and of lesions of midline structures. CSP became an interesting model opportunity for us, and allowed for the clinical, MRI and electrophysiological examination of developmental cerebral dysplasias. We believe that there is an important role for septal and diencephalic midline structures in cerebral electrogenesis, and possibly in the origin of epileptic seizures too.